Methane is the primary component of natural gas and represents an abundant, alternative chemical feedstock to petroleum. Methane is also a potent greenhouse gas, so excess natural gas from oil fields is flared in order to avoid releasing methane into the atmosphere. Converting natural gas and excess methane into liquid fuels and chemicals would be an efficient way to use natural resources and reduce greenhouse gas emissions. This conversion is challenging, however, when utilizing conventional thermal processes. Low temperature plasma reactor technology is an enticing tool for natural gas methane valorization to fuels and chemicals given its capability to activate hydrocarbons at much lower temperature than thermal processes. Not only does this bring potential to improve rates, but also opens the door to more desirable product selectivity. Despite its allure, practical implementation has been impeded by the complexity of the chemical, physical, and transport processes underlying the technology. This research project studies the valorization of natural gas using catalytic processes conducted in atmospheric plasmas. Little is known about the catalytic conversion of methane in plasmas, so understanding this process could translate into more sustainable chemical routes for methane conversion. The research project will be integrated with educational activities that train students to engineer solutions for sustainable energy, a future without pollution and waste, and reducing greenhouse gas emissions.
The research project aims to combine two technologies, plasma-promoted methane activation and transition-metal catalysis, to address methane valorization. The physical properties and chemical reactivity of atmospheric methane plasma are not well understood, nor are subsequent reactions of plasma products with transition metal complexes. Microfluidics techniques will be employed to generate plasmas with controllable properties. Then, experiments will be performed to probe the reactivity of plasmas with organic radical acceptors, to understand how plasmas interact with both organic radical acceptors and organometallic complexes, and to explore carbon-carbon and carbon-nitrogen bond formation in methane plasmas. The ultimate objective is to quantify the reactivity of plasmas with organic radical acceptors and transition metal complexes in order to convert methane into larger alkanes, substituted arenes, and amine compounds. Scale-up and intrinsic energy efficiency present potential challenges to the implementation of plasma-assisted chemical conversion processes. This study will uncover novel approaches for increasing methane reactivity and product selectivity to levels needed for translating fundamental findings into industrial applications.
This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
